Monitoring systems for monitoring areas forward of, around, and/or rearward of a vehicle using a camera or cameras are at a practical level as in-vehicle safety mechanisms. Such monitoring systems, in many cases, use radars or sonar devices as sensors in combination with cameras. An in-vehicle monitoring system includes an image input unit, i.e. a camera provided with an image sensor, an image processing unit to perform image processing, and a determination unit to perform processing for making determination. Generally, an in-vehicle monitoring system includes a processing unit for each sensor used in the system.
To monitor not only an area forward of a vehicle but also an area around or rearward of the vehicle, it is necessary to use as many image processing units as required in addition to a required number of cameras (image sensors). This causes a cost increase.
An in-vehicle camera capable of largely and sharply displaying an image of a particular area and also capable of displaying images of plural different areas at a time is disclosed in Japanese Unexamined Patent Application Publication No. 2012-131390. The in-vehicle camera can perform the above two types of operation by changing the orientation of a mirror positioned forward of an imaging element. According to the above patent document, the in-vehicle camera can display images of plural different areas simultaneously by adjusting the orientation of the mirror. To be more concrete, as described in paragraph 0041 of the patent document, an upper half portion of the imaging range of the camera images an area forward of the vehicle and a lower half portion of the imaging range images an interior portion of and an area rearward of the vehicle.
An in-vehicle camera capable of imaging plural objects is disclosed in Japanese Unexamined Patent Application Publication No. 2011-20669. As shown in FIG. 4 included in the patent document and described in paragraphs 0037 to 0039 of the patent document, an area forward of the vehicle is shown in an upper half of a screen and an interior view of the vehicle and an area rearward of the vehicle are shown in a lower half of the screen of the camera unit.